Revision as of 05:02, 27 February 2007

shady3d: 2 barrel joints + middle joint for 3D motion

truss structure where a shady3d is moving

New Shadys for 3-D climbing

This research introduces the concept of modular robots to reconcile this trade-off. Instead of a single, full-degree-of-freedom robot, multiple simpler modules can be used. A single module has fewer degrees of freedom than required for complete 3-D motion, but it can move in a 2-D plane and reach a goal position in many cases. If complete 3-D motion is necessary, multiple modules can connect to and cooperate with each other to reach a goal position and orientation. The robot we present is the extension of a specific truss-climbing application our group has been working on: window shading.
This 2-D Shady robot concept has been extended to a 3-D truss climbing modular robot system called Shady3D The design of the 2-D Shady robot has been modified to be able to escape from a 2-D plane. Based on the modified design, robot hardware including both the mechanical parts and electronics has been developed. We have also developed low-level control algorithms that control joint rotation and gripper operation, and high-level planning algorithms that enable the robot to navigate in a 3-D truss structure.

what's new?

Arbitrary motion with 2-shady3Ds

We can build a 6-DOF manipulator with two 3-DOF modules and a passive truss element, or a passive bar.

6-dof motion is possible by the cooperation of 2 robots

To realize this, we built a active free bar which was active in a sense that it emitted a infra-red signal for a shady3D to know where it was and what it was. Two shady3Ds are simultaneously sensing and grasping a one bar in the below movie.
File:shadywithbarFull.avi

let's build something

The below movie shows the procedure of the self-assembling of a truss tower. Twelve active modules and eight passive bars were employed to build a three-dimensional tower. The tower building is performed through the following steps.

-Four 6-DOF manipulators move to the base location of the tower and approach remaining four active modules to pick them up. Remaining modules hold passive bars to connect to the 6-DOF manipulators.

-The 6-DOF manipulators connect to four remaining active modules. The active modules held by the manipulators release the grippers gripping the ground trusses. Thus, each 6-DOF manipulator becomes a structure consisting of three active modules and two passive bars.

-The four structures formed in the previous stage arrange themselves in the desired poses. Then, they connect to their neighbors to complete the tower structure.